Advertisements
Advertisements
Question
If the teeth are not cleaned regularly, they become covered with a sticky yellowish layer W of food particles and bacteria. Since layer W covers the teeth, the alkaline liquid X secreted by glands Y inside the mouth cannot reach the teeth surface to neutralise the acid formed by the action of organisms Z on sugary food, and hence tooth decay sets in.
(a) What is W known as?
(b) What is (i) X, and (ii) Y?
(c) What are organisms Z?
(d) State one way of removing layer W from the teeth.
Solution
(a) W is the dental plaque.
(b) (i) X refers to the saliva, while (ii) Y refers to the salivary glands.
(c) Organisms Z are bacteria.
(c) Layer of W, i.e. dental plaque, can be removed by regular brushing of teeth.
APPEARS IN
RELATED QUESTIONS
Which part of the digestive canal is involved in:
Chewing of food ______.
Last molar tooth in human beings is called ______.
Fill in the blank.
In an adult human, there are a total of ___ teeth.
Write true or false for the below statement. Rewrite the false statements correctly.
Absorption of food takes place in small intestine
Differentiate between.
Mechanical digestion and Chemical digestion
Describe the human alimentary canal.
Who is telling a lie?
Appendix: Digestion is impossible without me.
List out the functions of the digestive system.
Why it is important to wear helmet while riding a bike?
Describe the alimentary canal of man.
